A method and an apparatus of this type are illustrated in French published patent application 2 386 359. In FIG. 2 of this document, a carbon tape 4 passes through a silicon bath 2 after passing through a slot 7 provided in the bottom of a receptacle 1 containing the bath. The tape 4 is tensed and is continuously drawn vertically by friction between two rolls. The two rolls 5 are situated above the bath and may, for example, be rotated about their axes in opposite directions to each other.
The drawing method illustrated by this document suffers from drawbacks. The pressure exerted by the rolls on the tape may cause fractures in the layer of deposited silicon. Further, it is difficult to prevent a tape being drawn in this manner from moving in its own plane from side to side about the drawing axis, thereby tearing the tape on the edges of the slot.
Preferred embodiments of the present invention mitigate these drawbacks.